The primary objective of this project is the bioregulation of the important insect vectors of human diseases in Pakistan. Genetic manipulation of laboratory-reared mosquito populations has produced strains with reduced reproduction potential and/or vector ability. Emphasis is placed on three vector species: Culex tritaeniorhynchus which transmits Japanese encephalitis, West Nile and Chikungunya viruses, and the major Pakistani malarial vectors, Anopheles stephensi and An. culicifacies. Several test areas have been throughly studied ecologically through the past year and will serve as release sites for the altered, non-vector or semi-sterile colonies.